TBI Issues

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cladiesel

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Alright, so i bought the gm1 to obd2 connector and I'm hoping to see what i can see this weekend. Still feeling a little optimistic about this but hoping i get a little insite as to whats actually happeneing
 

KnuckleBuster

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I'm leaning towards the distributor as my issue. I've been looking at the dui 12620bk as a replacement. Whats the pros and cons anyone thats run one has found
You put a new distributor in less than 5,000 miles ago and now you're considering putting another new one in?

I've seen a few ignition modules that caused continued injector pulsing after stalling. Every time it was a Wells brand (aftermarket) module. Been a long time. Surely they've fixed that by now.
 
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cladiesel

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You put a new distributor in less than 5,000 miles ago and now you're considering another new one in?

I've seen a few ignition modules that caused continued injector pulsing after stalling. Every time it was a Wells brand (aftermarket) module. Been a long time. Surely they've fixed that by now.
I've been having issues since about a year after new engine install. Its burned up 3 iginition modules so i opted for a new distributor. Still having issues but not with the module now.
 

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I really need to write some info on these distributors and modules that I can copy and paste into these threads instead of writing it fresh every time. 'bout time to go. Good luck and have a fun weekend!
 

cladiesel

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Just an update. It stalled again and the injectors kept spraying fuel. I unplugged the injectors and still head a noise. It was coming from the coil. So i sawpped it out with another that i had and now all seems ok. Still skeptical though.
 

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spraying by pulsing or just an even spray like the injectors are stuck open? the injectors shouldn't be pulsing unless the ECM gets a reference signal from the distributor with key on. maybe the injectors are stuck open, it is flooding and stalling, and still spraying fuel until the pressure in the line bleeds off?

if you have somebody watch the injectors and turn key on to prime the fuel lines, do the injectors push out fuel? if so, the injectors need to be replaced or maybe you can clean them.

also check to make sure the wires off the ignition control module aren't rubbed through and somehow sending reference signals to the ECM with key on power.

do the injectors keep spraying if you turn the key off?
 

Ricko1966

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@gmbellew aren't the tbi injectors a constant hot a and pwm ground side trigger? I f so if the negative side shorts to ground the injectors would continue to spray until power was cut. Just adding to what you posted. @cladiesel @gmbellew is giving you some very very good suggestions.
 

gmbellew

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@gmbellew aren't the tbi injectors a constant hot a and pwm ground side trigger? I f so if the negative side shorts to ground the injectors would continue to spray until power was cut. Just adding to what you posted. @cladiesel @gmbellew is giving you some very very good suggestions.

yes, constant hot and grounded by the ECM to pulse., but the injectors have separate wires off the ECM. so if they are both spraying they'd both have to be shorted to ground? most likely spot for that is at the air cleaner housing?
 

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yes, constant hot and grounded by the ECM to pulse., but the injectors have separate wires off the ECM. so if they are both spraying they'd both have to be shorted to ground? most likely spot for that is at the air cleaner housing?
I've got a hunch something like that is going. Chaffed power wires would result in no positive and a blown fuse. A bad distributor ecm would lose signal and injectors would die. An ecm failing I guess could short both injectors to ground,but an intermediate short in the injector harness just makes like a more likely candidate just from the difference in environment and exposur.
O.P. Engine running wiggle underhood harnesses especially in the TBI area,hopefully it will die. It won't run? Unplug the injectors check for 12v on 1 side,if you show zero continuity to ground, you have a wiring/ ecm problem.
 

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I had the same thing happen to me with injectors keep spray after truck stalled. 4 distributors later 3 different brands and it fixed my problem. One brand wouldn't even last a week. The one in now is a world products for a camaro firebird. Can't remember the first one.

The one time it kept spraying for 10 minutes and I had fuel coming out of everywhere. What a mess. Good thing it was winter and not hot out or I would of burnt the truck down.
 

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I had the same thing happen to me with injectors keep spray after truck stalled. 4 distributors later 3 different brands and it fixed my problem. One brand wouldn't even last a week. The one in now is a world products for a camaro firebird. Can't remember the first one.

The one time it kept spraying for 10 minutes and I had fuel coming out of everywhere. What a mess. Good thing it was winter and not hot out or I would of burnt the truck down.

it was spraying even with key "off"?
 

Ricko1966

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? How? It's keyed hot. Open circuit with key off.
 

cladiesel

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spraying by pulsing or just an even spray like the injectors are stuck open? the injectors shouldn't be pulsing unless the ECM gets a reference signal from the distributor with key on. maybe the injectors are stuck open, it is flooding and stalling, and still spraying fuel until the pressure in the line bleeds off?

if you have somebody watch the injectors and turn key on to prime the fuel lines, do the injectors push out fuel? if so, the injectors need to be replaced or maybe you can clean them.

also check to make sure the wires off the ignition control module aren't rubbed through and somehow sending reference signals to the ECM with key on power.

do the injectors keep spraying if you turn the key off

spraying by pulsing or just an even spray like the injectors are stuck open? the injectors shouldn't be pulsing unless the ECM gets a reference signal from the distributor with key on. maybe the injectors are stuck open, it is flooding and stalling, and still spraying fuel until the pressure in the line bleeds off?

if you have somebody watch the injectors and turn key on to prime the fuel lines, do the injectors push out fuel? if so, the injectors need to be replaced or maybe you can clean them.

also check to make sure the wires off the ignition control module aren't rubbed through and somehow sending reference signals to the ECM with key on power.

do the injectors keep spraying if you turn the key off?
Put brand ne ac delco injectors in it already
 

cladiesel

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So new icm came in today. Now waiting on collector with o2 bung so I can put o2 sensor back in it. It has ran without an o2 sensor for 15 years without one but who knows. Its worth a try i guess.
 

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